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A Thick Layer: A Fine-Tuned Critique of Arvin Ash

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Arvin Ash is an engineer with a YouTube channel. He recently posted a video titled “Is God in Physics? Fine Tuning Scrutinized“. It gets almost everything wrong: history, philosophy, science, and fine-tuning. All quotes from the video, unless noted otherwise.

A. Motion in the heavens

Until 350 years ago, there was a distinct demarcation between what people observed on Earth and what people saw up in the sky. There did not seem to be any connection. Things that happened on Earth could at least be seen and explained at least in terms of cause and effect. The Heavens seemed to be an utter mystery. The motions of the planets, though predictable, did not appear to follow the same patterns as objects here on Earth. To many this was the sign of the hand of a Creator. It must be God that ruled over the universe, controlling the movement of these heavenly bodies, and to gaze at the stars was to bear witness to the majesty of God’s design. [0:15]

We’re off to a terrible start. The Heavens were not an “utter mystery” to the ancients – Aristotle’s physics included the heavens. The planets and stars behaved differently to Earthly elements (earth, water, air, fire) because they were made out of different stuff.

More importantly, read any decent history of the debate over the existence of God: no one made this argument. No significant ancient or medieval thinker, whether pagan, Jewish, Christian or Islamic, not Plato, Aristotle, Plotinus, Augustine, Boethius, Avicenna, Maimonides, Aquinas or the Scholastics, argued from the difference of the Heavens to the Earth to the existence of God. This isn’t Plato’s demiurge, or Aristotle’s argument for a Prime Mover, or any of Aquinas’s Five Ways. The argument doesn’t even make sense: it would suggest that God was the maker of the Heavens but not the maker of Earth.

This is a familiar strategy: make yourself seem smarter by inventing a bogus argument and putting it in the mouths of your obviously clueless predecessors. From the very beginning, Ash ignores what people have actually said and instead concocts a convenient straw-man argument to knock over. Get used to it.

B. Newton

Ironically, Newton himself did not view his equations as negating the need for God. To him, the nature of gravity which he described as action at a distance, meaning a force that acts on things without touching it, was evidence that God still had a hand in the universe. [2:27]

On screen at 2:40 is,

“Gravity affecting something without touching it is evidence of God’s influence.”

Given that Newton’s ideas are being discussed, the quotation marks give the impression that this is a direct quote from Newton. But Newton said nothing of the sort. In fact, he denies such an idea in the General Scholium, an essay that Newton appended to the Principia. He notes a major gap in scientific knowledge:

Hitherto we have explain’d the phænomena of the heavens and of our sea, by the power of Gravity, but have not yet assign’d the cause of this power. – Newton

Aha! Newton should be about to tell us that the power of gravity is “evidence of God’s influence”, right?

But hitherto I have not been able to discover the cause of those properties of gravity from phaenomena, and I frame no hypothesis. For whatever is not deduc’d from the phaenomena, is to be called an hypothesis; and hypotheses, whether metaphysical or physical, whether of occult qualities or mechanical, have no place in experimental philosophy. – Newton

So, where does Newton see the hand of God? In action at a distance?

Eternal and Infinite, Omnipotent and Omniscient; … he governs all things, and knows all things that are or can be done. … We know him only by his most wise and excellent contrivances of things, and final causes; we admire him for his perfections; but we reverence and adore him on account of his dominion.” – Newton

In everything. God governs all things. More on Newton here and here.

As before, rather than actually interacting with the views of this great thinker, he makes up a quote from Sir Isaac Newton. You’d think the greatest physicist of all time would deserve more respect than that. Instead, he invents a conveniently bogus argument to knock over.

C. The Neutrino

… scientists point out that some of these are so finely tuned that even a slight variation would have resulted in a universe devoid of life. They point out for example, the mass of a neutrino is 2 x 10^-37 kg. It has been shown that if this mass was off by just one decimal point, that is if it was 2 x 10^-36 kg or 2 x 10^-38 kg, life would not exist because if the mass was too high, the additional gravity would cause the universe to collapse. If the mass was too low, galaxies could not form because the universe would have expanded too fast. [3:04]

Wrong.

This is a video about the fine-tuning of the universe for life, and the first and most discussed example is wrong. How difficult is it to actually read something on a topic before making an educational video about it? He could have picked any of Martin Rees’s “Just Six Numbers” or looked at “The Goldilocks Enigma” by Paul Davies (both excellent books). Of course, he could have read my book with Geraint Lewis as well.

But instead, he just made something up. That’s the only explanation I can think of. No scientific paper or book that I have read on the topic has presented this case.

[Edit: 17/9/2020 – I think I found the source. In his 1982 book “The Accidental Universe”, Paul Davies writes “… had the neutrino mass turned out to be, say, 5 x 10^-34 kg instead, then the gravitating power of the primeval background would have caused a drastic alteration in the expansion of the universe, possibly even halting it completely before now.”

Firstly, Ash gets the neutrino mass upper limit wrong by 2 orders of magnitude. Secondly, Davies chooses his words wisely: “possibly even halting”. It all depends on how the mass-energy of the neutrinos is related to the expansion. In an inflationary universe, it is always at critical density, and instead of a collapsing universe, we get a universe whose energy is dominated by neutrinos, at the expense of ordinary matter. This leads to the limits on the neutrino mass in the scientific literature.]

In the scientific literature, the limits on the neutrino mass are as follows.

  • If the total mass of the neutrinos is greater than about 10 eV (2 x 10^-35kg), then the formation of structure in the cosmos is strongly suppressed.
  • There is no life-permitting lower bound on the neutrino mass. It is false that the universe would have expanded too fast if the neutrino mass were too low.

This is sufficient evidence to conclude that that Ash has no idea what he is talking about. Rather than the physics literature on fine-tuning, or any competent book on the topic, he just makes up a conveniently bogus claim to knock over.

D. Units – a beginners guide

… the argument exaggerates the idea of fine tuning by using misleading units of measurement, to make fine tuning seem much more unlikely than it may be. You’ll see, for example, that the mass of neutrinos is expressed in kg. These things are so small that any fluctuation expressed in kilograms would be a huge fluctuation. … The kilogram measurement for the neutrino is arbitrary, a better measurement would be electronvolts or even picograms. [4:06]

Just consider the claim being made here. Fine-tuning cases were first discussed by the physicist Brandon Carter in 1973, and were catalogued in detail by Paul Davies in his book “The Accidental Universe” in 1982 and by Barrow and Tipler’s “The Anthropic Cosmological Principle” in 1986. They have been researched in the scientific literature in a multitude of papers ever since, as you can see in the 130+ papers cited in my 2012 review paper. Fine-tuning has been discussed in anthologies like “Universe or Multiverse?” (2008), and the forthcoming “Fine-Tuning in the Physical Universe“, by some of the greatest living physicists.

And apparently, all this time, we were all making an elementary error of units. You see kiddo, the engineer deigns to tell us, physical units are actually arbitrary. So when Stephen Hawking said …

Most of the fundamental constants in our theories appear fine-tuned in the sense that if they were altered by only modest amounts, the universe would be qualitatively different, and in many cases unsuitable for the development of life. … The emergence of the complex structures capable of supporting intelligent observers seems to be very fragile. The laws of nature form a system that is extremely fine-tuned, and very little in physical law can be altered without destroying the possibility of the development of life as we know it.”  – Hawking

… apparently Ash would have taken him aside and gently explained to him what kilograms really are.

No paper in the physics literature, no book on the topic by a physicist, and (almost) no discussion of fine-tuning in the philosophical or theological literature makes the elementary error that Ash alleges. We all use dimensionless quantities. We have since Carter in 1973. This objection is aimed at no one. Once again, rather than read seemingly anything at all in the physics or philosophical literature on fine-tuning, he invents a convenient claim to knock over.

E. Expected values of the constants

Most of the constants of the universe could not really be any arbitrary number. They are going to hover around some value close to what they actually are.  [5:47]

Are they? Well, that’s certainly news to modern physics. Because the cosmological constant problem says that the expected value for the vacuum energy of our universe is 120 orders of magnitude larger than the actual value. And the hierarchy problem of particle physics says that the expected value for the masses of the fundamental particles is about 20 orders of magnitude larger than the actual value.

But, great news, physicists who have struggled with these and other problems for a few decades! Listen up! The constants will probably be about what they are. Hurray!

There is a good reason why this “solution” to the fine-tuning problem cannot be found anywhere in the physics literature: because it was invented out of thin air by an engineer on YouTube. If someone had an argument or calculation showing why (for example) the mass of the electron had to be about what it is measured to be, they’d have a Nobel Prize for it.

F. The Anthropic View

The fine tuning argument also concludes that the universe must be fine tuned, based on the observation that if one of its properties were any different, life could not exist. It has to have exactly the properties that it has. The problem with this statement is that it presumes a narrow definition of life based on the Anthropic View that life has to be the of the kind that we see on Earth, in a universe that has properties of our universe. [6:19] …

… anyone who insists that our form of life is the only conceivable life, would be making a claim based on no evidence and no theory. [12:49]

  • No, fine-tuning does not only consider one of the properties of the universe; that’s a myth.
  • No, fine-tuning does not argue that the universe’s properties must be “exact”.
  • No, fine-tuning does not presume a “narrow definition of life”, or say that “life has to be the of the kind that we see on Earth”. As Martin Rees says, “even for the most open-minded science fiction writer, ‘life’ or ‘intelligence’ requires the emergence of some generic complex structures”. It’s about the complexity required by an conceivable form of life. See Chapter 1 and 7 of “A Fortunate Universe“.

Anyone who had actually read the literature or a competent book on fine-tuning would know this. No defender of fine-tuning insists or assumes that our form of life is the “only conceivable life”.

But even more bizarre is the use of the term “Anthropic View” to mean “life has to be the of the kind that we see on Earth, in a universe that has properties of our universe.” Now, as I’ve detailed elsewhere, there are some subtly different definitions of the “Anthropic Principle” floating around. But I’ve never seen anyone, in physics or philosophy, define or use the term “Anthropic” to mean “life has to be the of the kind that we see on Earth”. That’s not what “Anthropic” means in the context of fine-tuning.

I can only conclude that, once again, Ash has pulled this definition out of thin air. It’s another straw man.

G. The Strength of Electromagnetism

… if the strength of electromagnetism was slightly larger or smaller, it would mean that atoms would be slightly smaller or larger, respectively. This probably would not preclude atoms form being formed, or chemistry from taking place. Life could probably still exist, but it would just be different. [6:57]

Without defining “slightly”, this claim is trivial. Yes, sufficiently small changes have small effects. But the strength of electromagnetism (fine-structure constant, alpha) is everywhere in physics, from the sizes of nuclei and atoms, to the structure of molecules, to the interaction of light with electrons, to the stability of stars, to supernovae explosions, to the formation of galaxies. Thinking that you can just change the constant, make atoms smaller or larger, and everything will be fine, is naive to say the least. The value of alpha in our universe is 0.007. If alpha were 0.019, free protons would decay into neutrons, leaving no hydrogen in the universe. If alpha were larger than 0.1 or smaller than 0.0001, stars would not be stable. These aren’t the tightest fine-tuning limits on a constant, but they are still worth describing correctly.

H. Stenger

Physicist Victor Stenger did a study in 2000 where he varied these 4 constants to see what the potential universes would look like. He analyzed 100 universes in which he randomly varied the constants by 5 order of magnitude above, and 5 order of magnitude below their actual values in our universe. What he found was that over half the universes would have stars that live at least a billion years. [9:06]

Has Ash finally read some of the physics literature on fine-tuning? Nope. Stenger’s “study” was published in a philosophical journal of a humanist society. Why? Because it would have been laughed out of any reputable physics journal. I have discussed Stenger’s “study” in detail here and in my 2012 review paper. In short:

  • The model contains 8 high school-level equations, 6 of which are incorrect in some way: one is insufficient, two are irrelevant, and three are just plain wrong.
  • The model ignores many of the most widely discussed fine-tuning cases: cosmological limits including big bang nucleosynthesis and galaxy and star formation, the stability of hydrogen to electron capture, the stability of the proton against decay into a neutron, the limit on the electron/proton mass ratio for stable structures, electron-positron pair instability for large alpha, stellar stability, the triple-alpha process, and the binding and unbinding of the diproton and deuteron.
  • It uses an ad hoc, unjustified probability distribution function (PDF) for the constants. Worse, he biases the model by centring the PDF on the values of the constants in our universe.

The model is completely meaningless. Ash ignores all of the actual fine-tuning literature in actual physics journals, and instead presents a flawed “study” from a humanist philosophical journal.

Ash goes on to say:

[Stenger] found that if the mass of the electron was 100,000 times lower, the proton mass could be as much as 1,000 times lower to achieve the same minimum stellar lifetime. There are lots of combinations where you could vary two or more constant and still have viable universes. [9:49]

Once again, fine-tuning does not vary only one of the constants at a time; that’s a myth. Yes, there are other potentially life permitting combinations of constants. No, that does not mean that there are “lots” of them.

Furthermore, the mass of the proton is not a fundamental constant of the standard model. Its mass depends on the masses of the up and down quarks, the QCD scale and the strength of electromagnetism. And those constants affect many other properties of our universe. So just saying that we could lower the proton mass doesn’t specify how it is done or what other quantities are affected. The claim is essentially meaningless.

I. John Leslie

Philosophers like John Leslie, of the University of Guelph think that the universe had multiple tries before we happen to exist. [10:46]

I laughed out loud at this. In his contribution to “God and the Multiverse: Scientific, Philosophical, and Theological Perspectives“, in an essay titled “God and Many Universes”, Leslie argues that the universe itself is a thought of a divine mind. There are other universes because there infinitely many thoughts in infinitely many other divine minds. These divine minds exist by axiological necessity: they exist because it is good for them to exist, and that is enough for existence.

So, Ash appeals to the multiverse as an alternative to God, and then cites a philosopher who argues that there is a multiverse because infinitely many gods exist. Bravo.

(Reminder: Leslie’s brilliant book Universes is required reading for anyone who wants to talk about fine-tuning.)

J. The Future of Physics

Science may someday have a theory from which the values of the existing physical constants can be derived or explained. What looks like fine tuning may really be due to our ignorance of the underlying mathematics that would explain these constants. [11:40]

This misses the point of the argument. We look at the deepest laws of the cosmos that physics has established on solid evidence (the standard models), to see if there is anything rare or remarkable or noteworthy about our universe. And there is: the ability of our universe to support life is a rare talent in the set of possible universes represented by varying the constants.

Maybe future advances will change that situation. Or maybe our universe will turn out to be more fine-tuned than we think it is now. There is absolutely no reason to think that the advance of science will decrease the degree of fine-tuning of our universe. So it is this objection, rather than the fine-tuning argument, that is making a desperate, last ditch appeal to ignorance. The fine-tuning argument is simply following the best scientific information that we have.

K. Analogies are like Sunlight – sometimes you get burned

The fine-tuning argument seems to be saying something analogous to the idea that the Sun radiates light so that we can see where we are going. In fact, the human eye evolved to be sensitive to light from the sun because that’s what gave us an evolutionary advantage. The sun is not fine tuned for our eyes. Our eyes are fine tuned for the sun. Similarly, the universe is not fine-tuned for humanity. Humanity is fine-tuned to the universe. [12:11]

False. Our eyes are capable of detecting sunlight because there is a remarkable coincidence in the fundamental constants that means that the typical energy of a photon leaving a star is roughly the same as the energy to excite a chemical bond. (Specifically, light from the Sun straightens the bend in the molecule 11-cis-retinal, triggering a signal to the brain.) This was exploited by evolution, but it was not created by evolution. If the Sun emitted x-rays, which destroy chemical bonds rather than exciting them, the molecules that make up biological eyes would be destroyed by sunlight.

The claim that we are “fine-tuned to the universe” is similarly false. If the constants of nature are not right, no complexity can form. And so a replicating entity, capable of Darwinian evolution, couldn’t form in the first place.

L. Conclusion

Why did I bother to write this? Because Ash’s video currently has 76,000 views on a YouTube channel with 245,000 subscribers. As we have seen, it never actually interacts with the fine-tuning argument. It can’t even get one example of fine-tuning correct, let alone the argument itself. And yet, seventy six thousand people think that they know what the fine-tuning argument is and what is wrong with it. And they don’t.

There are interesting conversations to be had about fine-tuning, whether the argument is successful or not. There are informed, thoughtful critiques by physicists like Sean Carroll and philosophers like Neil Manson. I’ve tried to defend the argument in detail here. Unfortunately, a lot of people can’t get to the good stuff, the deep conversations, because know-nothing “experts” who couldn’t be bothered learning the first thing about the topic have surrounded it in a thick layer of misinformation and codswallop. Instead of thinking deeply about physics and ultimate explanations and minds and probability and naturalism and more, I have to explain that, yes, in fact, professional physicists do know how to deal with units and we have varied more than one constant at a time. Instead of walking through mountains, we’re hacking through weeds. What a wasted opportunity.


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